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I'm such a beginner, even though I kind of know a few things, that it's really hard for me to spot duplicates. I didn't even know if the potential form tag really belonged here. By the way, I think I said "読んで出来ます" (I can read it).
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hippietrailFeb 28 '14 at 5:58

4

読んで出来ます is not grammatical (at least not in the sense "can read").
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dainichiFeb 28 '14 at 6:29

@dainichi: Is it that できる has to be used in combination with ことが? I've spotted this in constructions in this and the previous question but I never learned that so don't know how to understand it.
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hippietrailFeb 28 '14 at 9:23

3 Answers
3

出来る is the potential form (〜えます form, if you will) of する. As such, in common usage the best practice is to use the native potential form for all non-する verbs and できる for the rest. Proper construction of the potential form is as follows:

Type I (〜う) verbs: Change -u to -eる (e.g. 行く => 行ける). This ending can also be further inflected (e.g. 行けます、行けない, etc.)

得{え}る or うる is more literary. ことができる is slightly more formal than られる and both fit for everyday use.

ことができる and られる can only be used to describe humans' ability so they don't fit well with non-volitional verbs (無意志動詞). える or うる can also be used to describe possibility. E.g. ×あられる ○あり得る

Both ことができる and られる can be used when you are not allowed to do something, you don't have enough knowledge or skills to do something, or you don't want to do something. But it seems that people tend to use ことができる when they are not physically unable.

There are very rare cases that ことができる can occasionally be used with non-volitional. られる cannot.

I just realized your えます might refer to the -(r)eる potential form rather than 得ます{えます}.

られる and -(r)eる are basically the same. But られる has more meanings than -eる, e.g. it can be used as a passive form.

-(r)eる works for almost all types of verbs, while られる generally only works with 一段動詞.

Although the meaning are the same, られる is longer than -(r)eる, which sometimes make it less favorable in certain situations. e.g.

As far as I can tell, there is no real difference between the potential form (-える or -られる, depending on the verb) and することができる: they can be used interchangeably. That said, in normal conversation, you'll probably hear -える/-られる used more often, since it's much shorter.

Also, する itself has no potential form, so it can be replaced entirely by できる. Thus, phrases like バスケすることができる can be shortened to バスケできる.